Projected line charge



I llmted States Patent [111 3,513, 52

[72] Inventor Alfred G. Hoyl, Jr., by change of name 794,371 7/1905Matthew [OZ/37.7 from Alfred G. Hoel, Jr., 1,242,838 10/1917 Morden102/22 507 Boston Bldg., Denver, Colorado 80207 1,900,624 3/1933Voortmann 102/22 [21] Appl. No. 385,899 2,433,875 1/1948 Walker 102/22[22] Filed Oct. 13,1953 2,675,882 4/1954 Bazzoni 102/22 [45] PatentedNov. 10, 1970 2,771,841 11/1956 DeFino 102/22 OTHER REFERENCES PROJECTEDLINE CHARGE Popular Science, Feb. 1944, pp.1 l9, Pulleys Place Giant 6Claims, 6 Drawing Figs. Bangalores' Primary Examiner-Samuel Feinberg[52] U.S. CI "1.62/22 lag/8997, Attorney w E Thibodeam T J Lynch, HarryM.

Saragovitz, Edward .1. Kelly and Herbert Berl [51] Int. Cl ..F42b 13/56,

F42b 15/06 [50] Field ofSearch 102/89, 20. ABSTRACT: A flexime linearexplosive charge comprising a 2L 37-7; sg/HM) length of flexible rope, aplurality of separate high explosive units encircling said rope andmolded thereto in equally [56] References Cited spaced end-to-endrelationship to each other longitudinally of UNITED STATES PATENTS saidrope, a flexible tubular cover enclosing said plurality of 224,0242/1330 M88011 l02/20 ex losive units, means bindin said cover to said r0e inter- P g P 395,881 1/1889 Cunningham 102/89 mediate said explosiveunits, and means to propel said rope.

Patented Nov. 10, 1 970 INVENTOR. Alfred E. HnY 1 'yaulnlfrllulll.IIIIIIIIIIIIIIIIIIIIIIII 3 ATTOENE Y5 PROJECTED LINE CHARGE.

The invention described herein may be manufactured and used by or forthe Government for governmental purposes without the payment to me ofany royalty thereon.

This invention relates to line charges for detonating hidden mines orthe like.

An object of the invention is to provide a device which can be projectedthrough the air by a rocket attached to and towing the forward end,thereof, and dropped on a field which is sown with concealed mines andthen detonated to explode the mines.

A further object is to provide a line charge which can be projected byrocket over jungle or dense underbrush, to clear a path therethrough.

Another object of the invention is to provide a device which can bepropelled by a torpedo through shallow water and detonated where thepresence of underwater mines is suspected.

Another object of the invention is to provide a device wherein theseparate units of a linear charge will not be separated by slipping onthe rope when they come in contact with the ground surface.

A further object of the invention is to provide means for protecting theleading end of the line charge from the blast of the towing rocketduring flight thereof.

A further object of the invention is to provide a detonator for the linecharge which can be initiated after the charge has come to rest on thetarget or along the path to be cleared of mines or jungle.

A still further object of the invention is to provide a device with aminimum of metallic parts so as to reduce the hazard to friendly troopsfrom flying fragments of the device.

Other objects and advantages will be apparent from the followingdetailed description and the accompanying drawings, in which:

FIG. 1 is an elevational view of a linear explosive charge, with someparts shown in section for better illustration.

FIG. 2 is an enlarged sectional view of two of the explosive units andtheir protective coverings.

FIG. 3 is a cross-sectional view taken on the line 33 of FIG.

FIG. 4 is a longitudinal sectional view of one type ol'detonator whichcan be used.

FIG. 5 is a sectional view of one method of attaching the forward end ofthe wire rope to a rocket, and

FIG. 6 is a sectional view of the method of attaching the rearward endof the wire rope to the flash deflector.

It has been found by tests that a linear charge of high or detonatingexplosives constructed according to the present disclosure is effectivein clearing mine fields on land and under shallow water, it is alsoeffective in clearing paths through jungle growths and in strippingcover from concealed defensive positions.

Heretofore linear charges have suffered great damage when projected ontorough terrain. In landing on any ground surface there is always atendency for the charge to slide a distance on the surface. This resultsin torn coverings and displaced explosive units, sometimes to a distancesufficient to prevent detonation of the forward parts of the charge.

In the drawings, wherein for the purpose of illustration, is shown oneform of the invention, the reference character 5 generally designates aline charge. Extending the full length and centrally thereof is a rope 6which may be made of nylon or any other suitable flexible materialhaving great tensile strength. At equally spaced positionsalong the rope6 any desired number of explosive units 7 are molded or otherwise formedor secured about the rope 6, centrally of said units. It has been foundthat a series of explosive units 300 feet long can be successfullylaunched by a rocket projectile and subsequently detonated. Enclosingthe said units from end to end is a fabric sleeve 8, preferably of wovennylon fabric material tied securely to the rope 6 between each explosiveunit by a nylon cord 8a as illustrated. or other suitable means. Any

preferred high explosive 9 can be enclosed in a waterproof jacket 10,such as cellophane, to keep the said explosive 9 dry and also to preventthe explosive from exuding through the fabric sleeve 8 when kept instorage for any length of time. If the present device is used to clearunderwater mines the sleeve 8 is also waterproofed. The final product isa flexible coilable line charge resembling a huge length of linksausage. A suitable and preferred dimension for the links is a length ofabout 6 inches and a diameter of about 3 inches, affording about 4pounds of explosive per linear foot.

The forward end of the rope 6 is looped about a pin 11 and secured toitself by braiding or other suitable means. The pin 11 is received inopenings 12 in the bifurcated ends 13 of a clevis 14. The clevis isformed with a frustoconical body 15 terminating in a reduced forwardscrew-threaded end 16 for receiving a similarly threaded nut 17, as bestshown in FIG. 6. The frustoconical body 15 fits in a similarly shapedseat 18 in the forward end 19 of a hollow blast deflector 20. The nut 17abuts a washer on the reduced screw-threaded end 16 and when drawn uptightly, snugly holds the rope socket 14 in its seat 18. A bore 21 isformed in the rope socket in its forward part and terminates in a flaredportion 22 rearwardly thereof to receive the spread ends 23 of a twistedwire towing cable 24. Molten solder is poured around said spread cableends to secure them in the rope socket. A rocket 25, schematically shownin FIG. I, has a bar 26 secured thereto and is bored at 27 to receivethe rearwardly extending reduced end 28 of a cable connector 29. Thereduced end of the connector is bored at 30 to receive the forward endof wire cable 24. The bore 30 terminates in a forwardly and outwardlyflared passageway 31 similar to the flared passageway 22 in the bodyportion 15 of rope socket l4, and receives the spread ends 32 of theforward end of cable 24 which ends are soldered in the manner aspreviously described. The reduced end 28 of the cable connector 29 isexteriorly screw-threaded to receive a nut 33. A circumferentialshoulder 34 on the connector abuts the bar 26 to resist drag of thecable when the line charge is launched and the nut 33 retains theconnector 29 in position.

The rear end of the hollow blast deflector 20 flares outwardly in afrustoconical form to deflect the hot propellent gasses of the rocketaway from the line charge 5. Surrounding the front end, and extendingrearwardly a substantial distance is a woven glass sleeve 35 whichadditionally protects the line charge from the hot gasses, and bothblast deflector 20 and sleeve 35 protect the front of said charge fromimpact damage when the charge contacts and snakes along the groundsurface in landing.

A detonator 36, having an explosive charge 37 therein is positioned onthe rope 6 and constitutes the final section of the line charge.Interiorly of the detonator which may be of light metal and generallytubular in form, electrical insulator sleeves 38 and 39 each receive asquib or blasting cap 40 each of which has its forward end embedded inthe explosive. The rear end of each squib is connected to a source ofvoltage (not shown) by the encased wires 41 and 42 of cables 50 and 51.Provision is made for two squibs if it is deemed desirable to prevent amisfire, but one may be used and the unused port can be plugged.

The operation of the device will be clear from the foregoingdescription. A length of line change, up to 300 feet or more is coiledso that it will pay out without kinking or knotting. A towing rocket isattached to the forward end as shown and the rear end of rope 6 issecured or anchored to any fixed object which may be a scow or stoneboat" on which the line charge is moved into position. The rocket isheld elevated by a suitable open-type launcher and is aimed in thegeneral direction of the path to be cleared. The rocket propellant isignited to launch the rocket and propel it with its attached linecharge, upwardly over the path to be cleared. The rocket propellant issubstantially exhausted by the time the line charge is fully extended sothat the charge falls over and along the path to be cleared. Thereafter,the circuit to one of the squibs 40 is closed to cause successivedetonation of the charges 9 thus clearing a path, or detonating anymines lying in or above ground along the path. If desired, prima cord,6a shown in broken lines in FIG. 2, may be secured to and along rope 6to assure continuity of explosion of the successive links. In such amodified construction it is proposed to use two lengths of prima cordbound together every 6 inches of length. Each length is cut in 10 footsections and placed contiguous the other length so that the abuttingends of one cut length are intermediate the abutting ends of the othercut length. In the assembled modified structure, the prima cord willextend along and in contact with rope 6 and may be secured theretosolely by the bindings 8a between links 7. Additional bindings may beused if desired.

While I have disclosed a form of the invention presently preferred byme, various changes and modifications will occur to those skilled in theart after a study of the present disclosure. Hence the disclosure is tobe taken in an illustrative rather than a limiting sense; and it is mydesire and intention to reserve all modifications falling within thescope of the subjoined claims.

Iclaim:

1. A flexible linear explosive charge comprising a length of flexiblerope, a plurality of separate high explosive units encircling said ropeand molded thereto in equally spaced end-toend relationship to eachother longitudinally of said rope, a flexible tubular cover enclosingsaid plurality of explosive units, means binding said cover to said ropeintermediate said explosive units, and means to propel said rope.

2. A flexible linear explosive charge comprising a plurality of highexplosive units, a length of flexible high strength rope having saidunits molded thereon centrally of said units, a waterproofed jacketencasing each of said units, a flexible tubular waterproofed fabriccover enclosing all of said plurality of explosive units, means bindingsaid cover to said rope intermediate said explosive units, means fordetonating a terminal one of said explosive units, and means to projectsaid rope and units over a path to be cleared.

3. A flexible lincur explosive charge comprising a length of flexiblehigh strength rope, a plurality of separate high explosive unitsencircling said rope and molded thereto in equally spaced end-to-endrelationship longitudinally of said rope, a-

flexible tubular fabric cover fitting about all said plurality ofexplosive units, binder means for binding said cover to said ropeintermediate said explosive units, a detonator element positioned onsaid rope in coincidental axial alignment with said rope and adjacent aterminal one of said explosive units, and explosive charge in saiddetonator element, means for initiating said detonator charge, and meansto project said explosive carrying rope over a path to be cleared.

4. A flexible linear explosive charge comprising a length of flexiblerope; a plurality of separate high explosive units strung on and alongsaid rope in equally spaced end-to-end relationship longitudinally ofsaid rope; a continuously extending flexible tubular fabric coverenclosing said plurality of explosive units; binder means forconstricting said cover intermediately of said units to preventdisplacement of said cover and units on and along said rope; a detonatorelement on the rear end of said rope adjacent the rear explosive unit; arocket for propelling said linear charge; and a flash deflector securedto the forward end of said rope, said flash deflector comprising ahollow body portion of greater diameter than said explosive units todeflect the blast from said rocket away from said explosive units; andmeans for connecting said flash cover and said rocket.

5. A flexible linear explosive charge comprising a length of flexiblerope, a plurality of separate high explosive units molded centrallythereof to said rope in equally spaced rela tionship to each otherlongitudinally of said rope, a continuously extending flexible tubularfabric cover enclosing said explosive units and rope, binder means forconstricting said cover tightly to said rope intermediately of saidunits, a detonator element on the rear end of said rope adjacent theterminal one of said explosive units, a rocketconnected with the forwardend of said rope for propelling said linear charge,

and means for protecting the forward end of said linear charge from theblast of said rocket and impact damage, said means comprising a hollowflared deflector body and a length of woven glass fabric enclosing theforward end of said charge and extending rearwardly a substantialdistance.

6. A flexible linear explosive charge as claimed in claim 5 including, aplurality of prima cord lengths extending between and connecting eachtwo explosive units. each said prima cord length lying parallel to andradially displaced from said flexible rope, and having its ends thereofterminating adjacent a corresponding end of one of said explosive units.

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